Fate of Pseudomonas putida after release into lake water mesocosms: Different survival mechanisms in response to environmental conditions

1994 ◽  
Vol 27 (2) ◽  
pp. 99-122 ◽  
Author(s):  
I. Brettar ◽  
M.I. Ramos-Gonzalez ◽  
J.L. Ramos ◽  
M.G. H�fle
Keyword(s):  
Pseudomonas Putida ◽  
Lake Water ◽  
Environmental Conditions ◽  
Survival Mechanisms

Holocene lake water-aquifer interactions in La Ballestera Playa-lake (southern Spain) recorded by stable isotopes (δ18O and δD) of gypsum hydration water

2021 ◽  
Author(s):  
Fernando Gazquez ◽  
Antonio García-Alix ◽  
Gonzalo Jiménez-Moreno ◽  
Francisco Jíménez-Espejo ◽  
Miguel Rodríguez-Rodríguez
Keyword(s):  
Stable Isotopes ◽  
Lake Water ◽  
Environmental Conditions ◽  
Sediment Cores ◽  
Southern Spain ◽  
Hydration Water ◽  
The Holocene ◽  
Playa Lake ◽  
Lake Evaporation ◽  
Southern Iberia

<p>Oxygen and hydrogen stable isotopes (δ<sup>18</sup>O and δD) of lake water are sensitive to long-term changes in environmental conditions, including relative humidity, temperature and the evaporation/outflow ratio of the lake. Lacustrine gypsum (CaSO<sub>4</sub>·2H<sub>2</sub>O) forms in equilibrium with its parent fluid, so the isotopic composition of its structurally bonded hydration water (GHW) can reflect the δ<sup>18</sup>O and δD of lake water at the time of mineral formation, with insignificant effects of temperature and salinity on the water-GHW isotope fractionation factors. Using the stable isotope content of gypsum-rich sediment cores as a paleoclimatic proxy, the environmental conditions prevailing in the lake setting at the time of gypsum crystallization can be investigated.</p><p>Here we apply this method to reconstruct the δ<sup>18</sup>O and δD of paleo-water in La Ballestera Playa-lake (Seville, southern Spain) throughout the Holocene, from 11.2 cal kyr BP to the present. Gypsum crystallization took place punctually at 11.2 and 4.4 cal kyr BP, and did continuously from 2.9 cal kyr BP to the present. The δ<sup>18</sup>O and δD showed the lowest values at ~11.2 cal kyr BP (2.3‰ and -1.1‰, respectively) and were significantly higher at ~4.4 cal kyr BP (8.8‰ and 29.2‰, respectively). Likewise, relatively higher values (8.2‰ and 29.8‰, respectively) were recorded at ~2.9 cal kyr BP. Thereafter, the isotopic ratios increased until the present (11.4‰ and 37.1‰, respectively), suggesting increasing aridity and/or hydrological closeness of the lake. A relative minimum in δ<sup>18</sup>O and δD occurred at ~2.3 cal kyr BP, during the wetter stage of the Iberian Roman Humid Period, while a relative maximum at ~1.1 cal kyr BP was recorded during the Medieval Warm Period.</p><p>We use a steady-state Isotope Mass Balance to investigate the paleo-hydrological conditions in the lake setting at different stages of the Holocene. Our results suggest that at ~11.2 cal kyr BP La Ballestera Playa-lake was a flow-through lake closely connected to the aquifer with and evaporation/outflow ratio <0.5. At 4.4 cal kyr BP and from ~2.9 cal kyr BP until the present, the system behaved as a terminal lake (evaporation/outflow ratio close to 1), with less connection to the aquifer and the main water output occurred via evaporation. The studied system turned into a playa lake because of a regional water table lowering. This most likely resulted from increasing aridity in southern Iberia during the late Holocene, which has previously been suggested by other lake sediment records in this region. </p><p> </p><p><strong>Acknowledgement</strong></p><p>This study was supported by the Junta del Andalucía PY18-871 to FG, the project<strong> </strong>CGL2017-85415-R of the Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER, the project B-RNM-144-UGR18, Proyectos I+D+i del Programa Operativo FEDER 2018 and the research groups RNM-189 y RNM-190 (Junta de Andalucía). Dr. Antonio García-Alix acknowledges the Ramón y Cajal fellowship, RYC-2015-18966. Fernando Gázquez acknowledges the postdoctoral “HIPATIA” program of University of Almería.</p>

scholarly journals Immune challenge retards seasonal reproductive regression in rodents: evidence for terminal investment

2006 ◽  
Vol 2 (3) ◽  
pp. 393-396 ◽  
Author(s):  
Zachary M Weil ◽  
Lynn B Martin ◽  
Joanna L Workman ◽  
Randy J Nelson
Keyword(s):  
Small Mammals ◽  
Environmental Conditions ◽  
Reproductive Function ◽  
Gram Negative Bacteria ◽  
Growth And Survival ◽  
Siberian Hamsters ◽  
The Face ◽  
Probability Of Death ◽  
Seasonally Breeding ◽  
Survival Mechanisms

Animals must balance investments in different physiological activities to allow them to maximize fitness in the environments they inhabit. These adjustments among reproduction, growth and survival are mandated because of the competing high costs of each process. Seasonally breeding rodents generally bias their investments towards reproduction when environmental conditions are benign, but shift these investments towards processes that promote survival, including immune activity, when environmental conditions deteriorate. Because survival probability of non-tropical small mammals is generally low in winter, under certain circumstances, these animals may not allocate resources to survival mechanisms in an effort to produce as many offspring as possible in the face of increased probability of death. Such ‘terminal investments’ have been described in passerines, but there are few examples of such phenomena in small mammals. Here, we show that male Siberian hamsters ( Phodopus sungorus ) challenged with lipopolysaccharide (a component of gram-negative bacteria that activates the immune system) induced a small, but significant, retardation of seasonal regression of the reproductive system relative to saline-injected hamsters. This delayed reproductive regression likely reflects a strategy to maintain reproductive function when survival prospects are compromised by infection.

scholarly journals Explorative Multifactor Approach for Investigating Global Survival Mechanisms of Campylobacter jejuni under Environmental Conditions

2005 ◽  
Vol 71 (4) ◽  
pp. 2086-2094 ◽  
Author(s):  
Birgitte Moen ◽  
Astrid Oust ◽  
Øyvind Langsrud ◽  
Nick Dorrell ◽  
Gemma L. Marsden ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Environmental Conditions ◽  
Dna Microarrays ◽  
Cell Envelope ◽  
Expression Patterns ◽  
Basic Knowledge ◽  
Ft Ir ◽  
Global Survival ◽  
Survival Mechanisms ◽  
Ft Ir Spectroscopy

ABSTRACT Explorative approaches such as DNA microarray experiments are becoming increasingly important in microbial research. Despite these major technical advancements, approaches to study multifactor experiments are still lacking. We have addressed this problem by using rotation testing and a novel multivariate analysis of variance (MANOVA) approach (50-50 MANOVA) to investigate interacting experimental factors in a complex experimental design. Furthermore, a new rotation testing based method was introduced to calculate false-discovery rates for each response. This novel analytical concept was used to investigate global survival mechanisms in the environment of the major food-borne pathogen C. jejuni. We simulated nongrowth environmental conditions by investigating combinations of the factors temperature (5 and 25°C) and oxygen tension (anaerobic, microaerobic, and aerobic). Data were generated with DNA microarrays for information about gene expression patterns and Fourier transform infrared (FT-IR) spectroscopy to study global macromolecular changes in the cell. Microarray analyses showed that most genes were either unchanged or down regulated compared to the reference (day 0) for the conditions tested and that the 25°C anaerobic condition gave the most distinct expression pattern with the fewest genes expressed. The few up-regulated genes were generally stress related and/or related to the cell envelope. We found, using FT-IR spectroscopy, that the amount of polysaccharides and oligosaccharides increased under the nongrowth survival conditions. Potential mechanisms for survival could be to down regulate most functions to save energy and to produce polysaccharides and oligosaccharides for protection against harsh environments. Basic knowledge about the survival mechanisms is of fundamental importance in preventing transmission of this bacterium through the food chain.

scholarly journals Rapid Immunocapture of Pseudomonas putida Cells from Lake Water by Using Bacterial Flagella

1991 ◽  
Vol 57 (2) ◽  
pp. 503-509 ◽  
Author(s):  
J. Alun W. Morgan ◽  
Craig Winstanley ◽  
Roger W. Pickup ◽  
Jon R. Saunders
Keyword(s):  
Pseudomonas Putida ◽  
Lake Water ◽  
Bacterial Flagella
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